Crop row detection system and agricultural machinery

Abstract

A crop row detection system includes a sensor to output sensor data including position information of an object, and a processor configured or programmed to detect adjacent crop rows based on the sensor data. The processor is configured or programmed to execute creating a map of crop rows in a vehicle coordinate system based on the sensor data, using the map to start an object detection search parallel to a second coordinate axis from a first coordinate point in the vehicle coordinate system to detect a left row and a right row of the adjacent crop rows. The processor is configured or programmed to, when updating the first coordinate point, increase or decrease the first coordinate on the first coordinate axis of the first coordinate point, and align a second coordinate on the second coordinate axis of the first coordinate point with a second coordinate on the second coordinate axis of a crop row center point, where distances to the left row and the right row of the adjacent crop rows are equal.

What is claimed is: 
     
         1 . A crop row detection system, comprising:
 a sensor attached to a vehicle configured to, when in operation, scan a surrounding environment including crop rows and output sensor data including position information of an object existing in the environment; and   a processor configured or programmed to detect, based on the sensor data, adjacent crop rows located on a left side or a right side of the vehicle among said crop rows, wherein: the processor is configured or programmed to:   based on the sensor data, create a map of the crop rows in a vehicle coordinate system that is fixed to the vehicle and that defines a coordinate plane including a first coordinate axis extending in a front-rear direction of the vehicle from an origin and a second coordinate axis extending in a left-right direction of the vehicle from the origin;   use the map to start an object detection search parallel to the second coordinate axis from a first coordinate point in the vehicle coordinate system to detect a left row and a right row of the adjacent crop rows;   consecutively update the first coordinate point and start an object detection search parallel to the second coordinate axis from the updated first coordinate point to detect the left row and the right row of the adjacent crop rows; and   when updating the first coordinate point, increase or decrease the first coordinate on the first coordinate axis of the first coordinate point, and align a second coordinate on the second coordinate axis of the first coordinate point with a second coordinate on the second coordinate axis of a crop row center point, where distances to the left row and the right row of the adjacent crop rows are equal.   
     
     
         2 . The crop row detection system according to  claim 1 , wherein the map is an occupancy grid map including a plurality of cells arranged in rows and columns, and height information of objects detected by the sensor is recorded in the plurality of cells on a cell-by-cell basis. 
     
     
         3 . The crop row detection system according to  claim 2 , wherein the processor, during the object detection search, is configured or programmed to use the height information recorded in the plurality of cells of the map to determine whether each cell is a part of the adjacent crop rows. 
     
     
         4 . The crop row detection system according to  claim 3 , wherein the processor, during the object detection search, is configured or programmed to determine whether each cell is a part of the adjacent crop rows by referring to information other than the height information recorded in the plurality of cells of the map. 
     
     
         5 . The crop row detection system according to  claim 1 , wherein the processor is configured or programmed to:
 determine a curve or a line segment that defines the left row based on position coordinates of the plurality of cells in the left row of the adjacent crop rows detected by the object detection search; and   determine a curve or a line segment that defines the right row based on position coordinates of the plurality of cells in the right row of the adjacent crop rows detected by the object detection search.   
     
     
         6 . The crop row detection system according to  claim 1 , wherein the position information included in the sensor data includes information indicating a distance from the sensor to the object and a direction of the object from the sensor. 
     
     
         7 . The crop row detection system according to  claim 1 , wherein during the object detection search, the processor is configured or programmed to perform the object detection search targeting an area of interest selected from the map to detect the left row and the right row of the adjacent crop rows from within the area of interest. 
     
     
         8 . The crop row detection system according to  claim 1 , wherein the crop row is a tree row. 
     
     
         9 . The crop row detection system according to  claim 1 , wherein the processor is configured or programmed to determine a self-position and an orientation of the vehicle on the map based on positions of the detected adjacent crop rows on the map. 
     
     
         10 . The crop row detection system according to  claim 1 , wherein the processor is configured or programmed to generate a target path for the vehicle to travel based on positions of the detected adjacent crop rows on the map. 
     
     
         11 . The crop row detection system according to  claim 1 , wherein the processor, based on positions of the detected adjacent crop rows on the map, is configured or programmed to determine an azimuth deviation and a lateral deviation of the vehicle relative to a center line of the adjacent crop rows on the map. 
     
     
         12 . An agricultural machine, comprising:
 the crop row detection system according to  claim 1 ;   a vehicle including the crop row detection system;   a propulsion device including a plurality of wheels including a steered wheel to steer the vehicle; and   an automatic steering controller configured or programmed to control a steering angle of the steered wheel, wherein   the automatic steering controller is configured or programmed to control the steering angle based on a position of the adjacent crop rows detected by the crop row detection system on the map.   
     
     
         13 . A computer configured or programmed to execute:
 acquiring sensor data output from a sensor attached to a vehicle and configured to, when in operation, output sensor data including position information of an object existing in an environment around the vehicle;   based on the sensor data, creating a map of the crop rows in a vehicle coordinate system that is fixed to the vehicle and that defines a coordinate plane including a first coordinate axis extending in a front-rear direction of the vehicle from an origin and a second coordinate axis extending in a left-right direction of the vehicle from the origin;   using the map to start an object detection search parallel to the second coordinate axis from a first coordinate point in the vehicle coordinate system to detect a left row and a right row of the adjacent crop rows;   consecutively updating the first coordinate point and starting an object detection search parallel to the second coordinate axis from the updated first coordinate point to detect the left row and the right row of the adjacent crop rows; and   when updating the first coordinate point, increase or decrease the first coordinate on the first coordinate axis of the first coordinate point, and align a second coordinate on the second coordinate axis of the first coordinate point with a second coordinate on the second coordinate axis of a crop row center point, where distances to the left row and the right row of the adjacent crop rows are equal.   
     
     
         14 . A non-transitory computer-readable medium including a computer program configured to cause a computer to execute:
 acquiring sensor data output from a sensor attached to a vehicle and configured to, when in operation, output sensor data including position information of an object existing in an environment around the vehicle;   based on the sensor data, creating a map of the crop rows in a vehicle coordinate system that is fixed to the vehicle and that defines a coordinate plane including a first coordinate axis extending in a front-rear direction of the vehicle from an origin and a second coordinate axis extending in a left-right direction of the vehicle from the origin;   using the map to start an object detection search parallel to the second coordinate axis from a first coordinate point in the vehicle coordinate system to detect a left row and a right row of the adjacent crop rows;   consecutively updating the first coordinate point and starting an object detection search parallel to the second coordinate axis from the updated first coordinate point to detect the left row and the right row of the adjacent crop rows; and   when updating the first coordinate point, increase or decrease the first coordinate on the first coordinate axis of the first coordinate point, and align a second coordinate on the second coordinate axis of the first coordinate point with a second coordinate on the second coordinate axis of a crop row center point, where distances to the left row and the right row of the adjacent crop rows are equal.   
     
     
         15 . A crop row detection method, comprising:
 acquiring sensor data output from a sensor attached to a vehicle and configured to, when in operation, output sensor data including position information of an object existing in an environment around the vehicle;   based on the sensor data, creating a map of the crop rows in a vehicle coordinate system that is fixed to the vehicle and that defines a coordinate plane including a first coordinate axis extending in a front-rear direction of the vehicle from an origin and a second coordinate axis extending in a left-right direction of the vehicle from the origin;   using the map to start an object detection search parallel to the second coordinate axis from a first coordinate point in the vehicle coordinate system to detect a left row and a right row of the adjacent crop rows;   consecutively updating the first coordinate point and starting an object detection search parallel to the second coordinate axis from the updated first coordinate point to detect the left row and the right row of the adjacent crop rows;   when updating the first coordinate point, increasing or decreasing the first coordinate on the first coordinate axis of the first coordinate point, and aligning a second coordinate on the second coordinate axis of the first coordinate point with a second coordinate on the second coordinate axis of a crop row center point, where distances to the left row and the right row of the adjacent crop rows are equal.